


Oxytocin

by SangSerrarium



Category: AI: The Somnium Files (Video Game)
Genre: Analysis/Buildup, Blood, Character Death, Gore, M/M, Psychological Drama, Psychological Trauma, Revenge Sex
Language: English
Status: Completed
Published: 2019-12-19
Updated: 2019-12-19
Packaged: 2021-02-26 00:53:59
Rating: Explicit
Warnings: Graphic Depictions Of Violence, Rape/Non-Con
Chapters: 1
Words: 2,884
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21854824
Author URL: https://archiveofourown.org/users/SangSerrarium/pseuds/SangSerrarium
Summary: Perhaps that’s what love was. A rush of blood. An irresistible surge of electricity. A short burst of euphoria that fizzled away, replaced by a gaping desire for more.And Saito had run all out of it.
Relationships: Date Kaname/Saito Sejima
Comments: 1
Kudos: 60





	Oxytocin

[1]

You were the next victim of the Cyclops Killer.

Well, perhaps you were expecting it. 

The chase was on. From the moment you noticed odd figures observing you from a distance, following you from behind before melting into the crowd. From the moment you felt rising paranoia with every step you took away from the city.

It was almost funny, how you nearly ran straight into him. His hands were slightly curled at his sides. His hair was a wavy mess that fell into his face. His suit jacket told otherwise of his status- and that was what alerted you. The way his neck tensed at his collar. The way lines were etched under his eyes and a sullen insanity loomed over his face. It was a cover that didn’t quite fit. A disguise. A restraint.

An unassuming lunatic, waiting to strike.

What struck you the most were his eyes. Hawkish in shape. A deep green that immediately set you on edge. You slowed down to a stop, your intuition screaming at you to _get away_.

He was almost beautiful, standing there, watching you from the lamplight. An eternity seemed to pass before he lowered his head and a curved smile crept onto his face.

Cold adrenaline.

Your instincts took over you, strength surged into your body- a kind of strength that emerged only at the moment of life and death.

Terror stabbed your heart with every beat. Your chest filled with a fluttering that threatened to fill your throat and choke you with air. Die. Death. This was it. You were dead, no, not yet, you had to fight- were you even running? It felt like you were falling, falling into solid darkness-

There was ballooning heat in your back as you ran. It grew hotter and hotter until it felt like it was burning you alive and, finally, you fell to the ground.

A knife.

Your eyes were a lovely shade of blue.

[2]

His father owned an estate in Tokyo. His assets totaled to billions of yen- enough to encompass a league of bodyguards and a traditional _minka_ near the Kabasaki district. 

He was a politician. A famous one too, enough to appear on TV. Not that money or fame mattered to Saito. It couldn’t have mattered less to him, to the stark contrast of his father.

He’d look back on that period of his life: that dream-like haze of his childhood. It was as much of a myth to him as the months he’d spent an aimless wanderer in Rohan’s body. Memories are fragments, forever floating in the human subconscious, possible to recover. Yet the pieces to that strange puzzle never came together.

He remembered two things with some clarity:

There was a time he heard noises coming from the basement stairs. It was dark down there- he never went more than a few steps before turning tail. But he went further this time.

He peered into a black bucket and saw a rat. They had rats in the basement, and one of the maids set a trap to catch them. It was stuck in some kind of glue and it was quivering inside, its shrieking diminished to pathetic squeals. When it saw him its beady eyes turned from side to side, its chest heaving to breathe. 

He didn’t know how long he stared before the maid saw him and led him away.

The second was his mother.

It was something that somehow, sometimes, compelled him.

He killed her. He knew that. He didn't take the burden of guilt. But So Sejima loved her. In a way, So’s affection for her transferred to their son when she died. For his son he could buy anything, give him an influential position in office if he wanted it, send him to the best schools- it was also for her, after all. His father was the main source of this strange, fickle love. If love was unconditional, then would his mother still choose to die for him if she had the choice? If love was special, then why did his father move on from them, to a mistress? 

There came a time when just watching wasn’t enough. He had to touch. Feel. Prod the delicate bones in the neck. Pull off the legs and see the fluid trail behind. Feel the resistance of a pair of scissors against the wings of a pigeon.

Perhaps that’s what love was. A rush of blood. An irresistible surge of electricity. A short burst of euphoria that fizzled away, replaced by a gaping desire for more.

And Saito had run all out of it.

He heaved the knife above his head, flecks of blood flying into his face as he drove his fists down again and again. The blade caught on the edges of her clothes, met some resistance deeper into the meat- but it was so slick that it dipped in and out with little need for twisting.

A furious heat rose to his face. His pupils were blown open wide as his vision turned red, the woman’s soft and pliant back sending his mind into a frenzy.

By the time he stopped stabbing, she was stiff in a pool of crimson.

His father didn’t stop him. So watched it all happen- watched his son run up behind her, drive the knife deep between her shoulder blades, pin her down to the cement and do it over and over and over again. He didn’t press charges. He didn’t so much as say a word.

Instead, he rushed to the yakuza. When he returned he told Saito that nobody would know. The body would be disposed, the evidence incinerated- and no-one was to ever speak of her again.

Saito knew how it all worked.

Manaka’s death was the next catalyst. So's attention would divert onto Saito, before it would dissolve again and have to be re-ignited.

Or would it lavish onto _their_ child?

Love, he decided, was _death_. It was what brought his family together. It was what ended suffering. It was what made life meaningful- who could live forever, after all? Who could live without purpose?

That kill brought him a soothing kind of happiness. It was a pure, light feeling, like a sunbeam gleaming through rainclouds- a smile graced his face, he laughed, he talked with an unabashed enthusiasm with others at school and the guards at home, to which they were pleasantly surprised.

Of course, that happiness quickly faded away.

Fireworks and sparklers, fire and combustions and the like... were much the same way.

He saw them in the sky during festivals and at the end of the events So spoke at. The fractured light filled his vision for a second or two and came with a loud _pop_. His curiosity led him to wonder what would happen if it came too close to a person, although he deemed the idea too outlandish for any use.

That would change when he later got his hands on a gun.

But that was all with Rohan.

"Cyclops Killers"...

If the media was fishing for notoriety with his eye collecting, he supposed they'd use a silly name like that.

The partnership itself wasn't the issue. The thing was, someone had tried to trick him. During those days of victory, an imposter appeared to send him crashing down:

**The imposter was HAYATO YAGYU. KANAME DATE.**

The thief of his mind.

A killer.

An innocent man, until he had nowhere left to run.

Trapped within hospital walls, the ever-present possessiveness took hold of Saito. Rage. _Vengeance_. A burning desire to reach the man and take back what was _his_.

Fireworks were beautiful things, but they were still made of _fire_. To deny Saito his happiness was to deny him his humanity. Those months he spent in other bodies, the slow, meticulous rebuilding of his psyche- if it weren't for his singular need for revenge, he truly would have faded into nothingness.

Of course, he could still murder. It was the easiest it had ever been, murder, when he could switch bodies with his victims. But there was a crucial error.

When he killed...

He felt _awful_.

His chest constricted, his throat tightened, a wave of nausea gripped his stomach. _He was trapped within the dysfunctional bodies of_ _this_ _inane world._

If there was a hell, he was in it. Relief. He needed _relief_.

But ironically, Saito Sejima was not a man who let emotions get in the way of his work.

His talent for death hadn't diminished.

From Shoko he could get Renju. From Renju he could get Iris. From Iris he could get So and from So he could get Boss and from Boss he could get _him_ \- with the prototype Psync, he could do it all right under the police's nose.

Well... everybody's nose but _Kaname Date's_ , he supposed. His detective work was impressive.

But all it did was lead him right to where he wanted him.

[3]

Recently, you realized your name was not Kaname Date.

The revelation didn't have much time to sink in- not with Saito fucking you with what felt like pure hatred.

It wasn’t uncommon for him to feel this way while killing- but to experience such a powerful urge, such a violent desire to ravage you while you were still alive?

The process of murder was a deeply personal, sacred rite. And you denied him his high, over and over again. You were the first to escape. The first to win. The first to leave him at the mercy of your theft, to make him feel like he was trudging through hell just to reach you. While he struggled with you, he was powerless.

You were as innocent as him, weren't you? You had as many reasons as him, didn't you? You did it all for _love_ , _didn't you?_ **_You and him were one and the same._ **

“ _YOU_ ,” he growled, pounding into you without mercy- “ARE. **_NOTHING_**.” His hand pressed against your collarbone, your pulse fluttering against his palm.

And so it all came down to this.

You lay there and took it, fists clenched, eyes squeezed shut. Each sharp jolt of sensation came with his hips slamming against the backs of yours, your bodies connecting with a harsh thud, the cloth of his pants scratching your naked thighs. 

There was a piercing pain in your left eye, the stench of fresh blood overwhelming. You could hardly think. You were still reeling from the Somnium you experienced- the nightmare was real, the nightmare of being trapped, of being the vessel of your worst enemy-

In every single way, this man had violated you.

Your body. Your mind. Your memories. Your friends, your family. Everything. He'd taken it all away.

You muttered something under your breath- a prayer. You told Mizuki you didn't believe in God and all, but... you wish you could have seen it. Seen your prayer back at the temple come true...

At least Aiba didn't have to watch.

Heh, Aiba...

She was nearly gone too, wasn't she? Her data...

You could make out his arm close to your face, his fist clenched against the ground. The cold cement of the floor pressed against your cheek. It was almost comforting, knowing you weren't able to fall any further. You shuddered as he lowered his mouth to the side of your neck, his breath tickling the skin there as he spoke:

_“How does it feel? To be back in your old body?"_

He punctuated the statement with a thrust and you winced in pain, speechless.

He answered, nearly hysterical with pleasure. "Because for me... it feels _amazing_."

Your insides were being set alight. It was sending you into delirium, the sheer amount of conflicting sensation. In the haze of it all you considered fighting back- but the thought slipped away as he pinned your wrists above your head and bit, _hard,_ into the flesh between your neck and shoulder. 

You let out a shout of surprise, unable to stop yourself from making noise. You knew it would only push him further- and it did. He grabbed your chin, turning your head around to make you look into his eyes. It was _your_ face you were staring into. What was _once_ your face, now twisted and demented.

A shard of your past beamed through your head like lightning.

Iris Sagan.

_My little girl._

Hitomi Sagan.

_I was in love._

Rohan Kamukura.

_I shot him._

Hayato Yagyu.

_A killer._

_"Hitomi,"_ you whispered.

His eyes widened before recognition swept over them.

Something surged through you. The strength that emerged only at the moment of life and death. All this time, all this _goddamn time_ -

"Date... I was hoping you'd remember..." He pressed you harder against him. His next words turned your blood to ice: "... because she's about to get blown to pieces."

**No.**

Your voice cracked as you spoke.

" _Don't fucking touch her. Don't lay a finger on her or I'll fucking kill you."_

**You can't die. You can't die now. Not when they're here, not when they're all right here-**

"Would it console you if I gave you a choice?"

You felt the cold barrel of a revolver press against your temple, and you knew it would all be over soon. 

"You can die now, and not know if she does as well. Perhaps I'll even let her live, if your death satisfies me enough. Or-"

The barrel dug into your skin harder. "... You can live a little longer. You can watch her execution with me, after I'm done with you. Which one sounds like the better option?"

You couldn't speak.

Saito chuckled before bursting into laughter, clawing your waist so hard you thought he'd draw blood. "No answer? I'll help you decide."

His finger twitched against the trigger.

" _Say it to me._ "

You were both the unwitting assassins of fate.

Did one killer deserve to live over another?

You were blackmailed, kidnapped, tortured, bombarded with threats to your life. There was criminal scum in this world that needed to be cleansed. Justice to be dealt to those who escaped the law. And when your old idealism fell apart, you realized you had a family to protect from your own actions.

It became a rhythm. A brutal monotony of daily life. You felt nothing when you pulled the trigger.

And what excuse did Saito Sejima have?

"Oxytocin."

....

"...What?"

"Oxytocin," you repeated, your voice quivering. "You're... You're deficient. I-In oxytocin. I know. And if-"

The gun jabbed against your head. You sharply inhaled.

"Of course, Hayato. You felt it, didn't you? The craving?"

This was it. He was still wearing Aiba- this was your chance. 

"Yes, I felt it. I felt everything you did, But I cured it. I-"

"Of course you did," he sighed, his fingers trailing along your jaw. "Of course you did. But your soul was too righteous to act, wasn't it?

"You can fix this. You can fix _all_ of this." The urgency in your voice climbed with every word. "I can give you oxytocin, dopamine- a continual dose- exactly what I did when I was in _your_ body-" 

....

He pulled away. You nearly cried out from relief- the pressure in your core was unbearable. He kept pressing the revolver against your head as he re-clasped his belt.

"I'm surprised there's resistance left in you," he said. The manic heat from earlier had vanished. Now he was as sterile as ice. "Perhaps you don't fully understand your dilemma."

"Saito, _listen to me_. How else did I live in your body? How else could I still feel happiness without resorting to _murder?_ "

His response was curt. "This isn't a matter of our brains. The Psync proves it all. You remember that stunt six years ago _,_ don't you? It only transferred our egos, the very essence of our personalities- and look how much _better_ I've become."

" _Please_ let me-"

" _Killing_ is a part of our _souls_ , Hayato. Nothing will change that. They will never understand."

"Let me give it to you," you rasped. "Oxytocin. Give me one chance. One chance."

He smiled, leaning in. "I am."

Saito was too close. 

"Well? I'll count down from three. Wait any longer to act and you might not get to see Hitomi again."

 _Aiba_. "Three." _Aiba!_ "Two." You chanted over and over in your head: _Aiba- p_ _lease. With the last of your energy, please..._

"One."

"Aiba! _**Do it!**_ "

The world stood still.

Saito's eyes widened.

His breath hitched, his expression softened, dissolving into stunned clarity. The gun fell from his hand and he stumbled backwards.

He was lost.

**Now—**

You raised the gun and, for a brief moment, closed your eye. 

And all you saw was the color **red**.

In that moment, the first thing that rose from your heart was an overwhelming **wrath** for the man in front of you.

The man you were about to shoot through the head.

" _I... I_ _hope you're goddamn happy now, Saito,_ " you breathed, your resolve shattered into pieces. "I hope there's a special place for you in heaven."

.

_Pop._

Fragments.

Fragments blazed across the world in the briefest moment of time. The last flicker of the universe before it detonated, drifting away into nothingness.

The tiniest moment of love, before it was torn away.

**Author's Note:**

> Be seeing you, you tragic evil oxytocin-deficient body-swapping bastard.


End file.
